1. Technical Field
The present invention relates to a vehicle occupant protection device, and particularly to a gas generating material which is useful in the protection device.
2. Description of the Prior Art
An inflator for inflating a vehicle occupant protection device, such as an air bag, contains a body of ignitable gas generating material. The inflator further includes an igniter. The igniter is actuated so as to ignite the body of gas generating material when the vehicle experiences a condition, such as a sudden deceleration, which is indicative of a collision for which inflation of the air bag is desired. As the body of gas generating material burns, it generates a volume of inflation gas. The inflation gas is directed into the vehicle air bag to inflate the air bag. When the air bag is inflated, it expands into the vehicle occupant compartment and helps to protect the vehicle occupant.
U.S. Pat. No. 5,060,973 discloses a vehicle occupant restraint apparatus which comprises a liquid gas generating composition. The composition comprises 60% hydroxyl ammonium nitrate (HAN) as an oxidizer, 20% triethanol ammonium nitrate (TEAN) as a fuel, and 20% water. The HAN and TEAN are water soluble.
U.S. Pat. No. 5,223,057 discloses a liquid monopropellant suitable for underwater and surface propulsion of ordnance vehicles. The composition comprises a solution or emulsion of hydroxyl ammonium nitrate (HAN), a water soluble or water dispersible fuel, and water. A number of fuels are listed such as alcohols, glycols, and amines. The amount of water is about 5% to 100% of the combined weight of fuel and oxidant, and functions as a desensitizing agent for the HAN and serves to provide cooling to control the flame temperature of the combustion reaction.
U.S. Pat. No. 5,451,277 discloses a method for preparing solid energetic compositions using liquid oxidizers. Hydroxyl ammonium nitrate (HAN) is listed as a suitable liquid oxidizer. Solid fuel particles such as a metal fuel are coated with a polyvinyl alcohol coating. The polymer-coated particles are dried and then combined with the liquid oxidizer forming a dispersion. The dispersion is cast into a mold. The liquid oxidizer is absorbed by the polymer coating causing aggregation of the dispersion into a rubbery solid mass.
U.S. Pat. No. 5,684,269 discloses a liquid gas generating composition suitable for automotive restraint systems. The composition comprises HAN and a nitrate salt of an amine such as an amino tetrazole.